On Comcast (Boston area) most videos are coming from 208.117.0.0/16 (ish) although some coming from the mentioned blocks. Interestingly for me the domain the v

On Comcast (Boston area) most videos are coming from 208.117.0.0/16 (ish) although some coming from the mentioned blocks. Interestingly for me the domain the videos are coming from are all of the same general form: > r1.sn-jvhj5nu-p5qd.c.youtube.com (where the bit before c.youtube.com varies) Where as the reddit discussion has domains of the form: > o-o---preferred---sn-mv-p5qe---v17---lscache1.c.youtube.com The inclusion of the 'preferred' and 'cache' bit are somewhat interesting. I did find that if I block 208.117.0.0/16 as well as the other two mentions blocks (173.194.55.0/24, 206.111.0.0/16) then no youtube videos will load at all. I would venture a guess that blocking the mentioned ranges is just forcing you to the 208.117.0.0/16 CDN.